He initially thought those poacher Animagi were all aggressive, or perhaps there was some restriction.
But it wasn't until he studied that dharma gate that he understood that it wasn't that they could only transform into aggressive carnivores, but rather they believed these carnivores offered better value—which is why, when he encountered those poachers in the Forbidden Forest a century ago, most of them would transform into the fierce (wild) wolves (dogs) of the Forbidden Forest.
Because these creatures are the easiest to catch, just like Pikachu in the Pokémon World.
However, this dharma gate also seemed unable to transform into Magical Creatures, since it's an Animagus, it must comply with the law of being ordinary animals.
Targeted transformation—after understanding this, William immediately felt those stupid poachers were wasting resources, you know, one of the reasons he's never tried becoming an Animagus was because the process is too cumbersome, and another is because it might be useless.
After all, what's the use of transforming into a cat with no combat power?
Petting yourself?
But that sort of thing, he could do in human form too (big cough)—
But now, a reason has appeared, with targeted transformation, it means he won't transform into a useless form—before that, he naturally has to try the non-targeted first, like drawing cards, use up the free draws first, not satisfied then use targeted to replace it—of course, the best outcome of this plan is he will have two transformation forms simultaneously.
More than a Transformer, just thinking about it feels awesome!
...Ahem, getting off track, as for why he plans to find Professor McGonagall, it's actually to lay a smoke screen for the potential second form that may exist later and also to show Dumbledore that I'm a law-abiding good citizen—the latter being the main point.
William clearly knows that although he gets along well with Dumbledore now, that century-old man has been wary of him—
To be honest, if he were in Dumbledore's position, he couldn't completely trust someone like himself who suddenly appeared either, after all a powerful person who seems to have no desires is too...uh, terrifying, so William plans to keep himself busy, within the legal boundaries.
Because illegal busyness cannot be seen by Dumbledore.
And Animagus is a very good busyness point, requiring not only holding a mandrake leaf in the mouth for a whole month, but also moonlight on the second full moon, followed by transformation during an impending storm, and until that storm he needs to recite a spell at sunrise and sunset every day...
Yes, it's too troublesome, that's also why there are so few Animagi now.
Although he's not short of Mandrake, William still received the small paper package handed to him by Professor McGonagall, so the Greater Death's Head Hawkmoth chrysalis and the dewdrop untouched by sunlight for seven days could also be collected by Professor Meow—this doesn't count as exploiting labor, after all, Professor McGonagall seemed quite happy to help him learn this.
Today is not a full moon, so after chatting with Professor Meow for a bit, William left the Transfiguration Class classroom full of regret.
Because Professor McGonagall doesn't want to transform into a cat…
...
"...Divination class is just a mess."
After William finished another Herbology class, leaving the greenhouse full of harvests, walking into the hall, he saw Hermione sitting near the entrance, noisily flipping through the textbook beside her, "I say, it's just wild guessing."
"That omen in the cup is not just a pile of nonsense!" Ron said excitedly beside the girl.
"You didn't sound so sure when you told Harry it was a sheep." Hermione's tone turned cold.
"Because Professor Trelawney said you don't have the right aura! You just like to act tough, unwilling to admit you can't do something!"
This seemed to hit a nerve for Hermione, the girl slammed her Arithmancy textbook on the table with a WHACK, too hard, sending mince and carrot crumbs flying all over, causing Kabuda, who was enjoying lunch in front of Ginny, to squeak in discontent.
"If learning Divination means I have to pretend to see some Death Omen in a pile of nonsensical tea leaves, then I might just stop taking it! Compared to my Arithmancy class, this course is just garbage!"
Hermione grabbed her heavy backpack and stormed off.
"What's she talking about?" Ron frowned, watching her depart. "She hasn't even taken Arithmancy yet."
"So, what are you talking about? What omen?"
William stood behind the two, then reached out to pin down the escaping Kabuda to the table, and started furiously rubbing his belly, discovering a few bottles of the Magic Potion in his pouch...
No, need to make Kabuda pause this, otherwise, Snape might be stolen bankrupt—need to learn sustainable exploitation.
William turned to the teacher's table not far away, Snape's expression was complex, his figure hunched low, looking around suspiciously, occasionally casting hateful glances at Lupin chatting with Professor Flitwick at the other end of the table.
...Given Snape's current level of anxiety and mood, if the Niffler crashes, consequences would likely be unthinkable.
Looks like it really needs to be stopped for now.
"Omen!"
Hearing William's question, Ron repeated exaggeratedly, then quickly lowered his voice, explaining mysteriously, "Harry said he saw an omen, it was a big black dog—and today, Professor Trelawney saw an omen in his tea cup—"
"In Diagon Alley, the night two days before the start of term."
Harry nodded, adding when he saw the omen, then, looking a bit hesitant, he continued, "William, is the omen real?"
The boy's expression was extremely tense, his face even a bit green... oh, wait, that might be because his head was still emitting green flames.
"If black dogs are all omens, wouldn't there be too many unlucky people in the world?"
William frowned—a big black dog, aren't those everywhere? He had several living next door in his previous life, sleek and smooth, if seeing black dogs meant croaking within twenty-four hours like Ron said, wouldn't the whole village be dead?
Moreover, he's always been skeptical of those absurd prophecies—even the one Dumbledore mentioned before, frankly, he didn't really believe it at all.